> Yeah, I'm suspecting there's a loophole in the logic there somewhere.>> I dusted off the 6041 reference card I have here, and played with the cables for a while. Managed to > get one port to stop responding to hot plug fairly quickly, though I'm not sure how/why.>> Then I added a debug printk() to mv_write_main_irq_mask(), with no other changes, and that appears to > have been enough to change the race timing so that I could no longer produce the problem.>> Bruce, here's a slightly-ugly patch that should remove all doubt about races in the irq_mask. Please > apply it, test with it, and let me know here if the issue goes away.>> Thanks

Thanks Mark. I was about to try out some tracing in writelfl because Isuspected the irq mask was getting clobbered somewhere along the way, butI'd been distracted by other work. I shall try your patch out as soon asI can, and report back.